DHCP Server and IP Address Assignment

Dnsmasq is running on kabru to provide DHCP services for the lab (room 4776) network (10.0.0.0/24). It also provides services for room 4956 network via a customized DHCP relay running on howie. IP addresses of VPN hosts are managed by VPN server (OpenVPN).

Domain Name

RTCL network uses rtcl as the domain name (DNS suffix). The DHCP server also resolves DNS queries, including reverse queries.

IP Addresses

For machines that has its Ethernet MAC address registered in /etc/ethers and /etc/hosts on kabru, the same IP address will be given out whenever the machine makes a DHCP request. Unregistered machines will get an IP address from 10.0.0.240-254 or 10.10.0.240-254. Although the DHCP server will try to assign the same IP address to unregistered machines, registering with DHCP server is the only method to ensure fixed IP assignment.

DHCP Options

The DHCP server will send out several configuration parameters with each reply. Using these parameters enables host auto-configuration and also makes future configuration changes easier to be incorporated. Configuration files, such as /etc/sysconfig/network/dhcp in openSUSE Linux, might need some tweaks to maximize the benefits. Network-related DHCP options include:

• Netmask (255.255.255.0)
• Default gateway/router (10.0.0.1 or 10.10.0.10)
• DNS server (10.0.0.1)
• DNS domain search list (rtcl, eecs.umich.edu)
• NTP server (10.0.0.1 or 10.10.0.10)

-- Main.chtsai - 01 Mar 2007